feat(dictation): recover Esc-cancelled recordings - #989

Summary

• make Esc recording recovery an explicit macOS/Windows recording setting that is off by default
• keep the original direct-cancel behavior when the setting is off: no recovery history entry and no Continue capsule
• when enabled, preserve WAV audio and a pending history entry, then let the user continue the same recording or transcribe it from history
• dismiss an already visible/pending recovery capsule immediately when the setting is turned off, without deleting audio that was already saved
• retain second-Escape dismissal, flash-free double Escape, and paced PCM replay for Qwen realtime ASR
• merge the latest beta and preserve its Windows selection-voice session guard

Esc routing decision

OpenLess currently observes Esc through a global OS-level event tap before the foreground application handles the key. At that point it can either suppress the event or pass it on, but macOS does not send a later acknowledgement indicating whether a browser/AppKit responder consumed it. Browser bubbling and preventDefault() are internal to the browser process and cannot propagate back to the event tap.

Apple documents the same boundary for event monitors: a global monitor cannot modify/prevent delivery, while a local monitor only controls events dispatched inside its own app. Therefore “let the foreground app consume Esc first, then cancel OpenLess only if it remained unconsumed” is not reliable for a cross-application voice input tool.

• Monitoring Events
• Event Architecture

The opt-in setting is retained as the deterministic behavior: users who want recoverable Esc cancellation can enable it; everyone else keeps direct cancellation without a recovery capsule.

Behavior

• default/off: Esc stops and discards the current recording through the existing cancellation path; no recovery UI is shown
• enabled: Esc stops recording, saves the captured audio locally, writes the pending history entry, and briefly offers Continue
• Continue: resumes the same session with the previous PCM prepended to the new microphone audio
• second Esc: dismisses the recovery capsule; a rapid double Esc skips showing it
• turning the setting off dismisses any pending recovery prompt; recordings already persisted are kept for history integrity

Verification

• GitHub CI: Android, Linux, Windows, and macOS all passed
• Rust library tests: 1274 passed, 7 ignored, 0 failed
• frontend and contract test runner: 60 passed
• Qwen realtime Rust tests: 26 passed
• Esc bridge Rust tests: 4 passed
• recovery preference/gating Rust tests: 3 passed
• production frontend build passed
• git diff --check passed